Can't speak for you car, but mine had the same leak.

Had to:
1) drain oil,
2) jack up the engine so as to be able to remove pan,
3) remove sender unit, which pulls out,

in order to replace two (2) o-rings. Now, no leaks.
Painful way but I HATE LEAKS! Probably should buy a Lexus! Maybe there's an easier way?

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Regards . . . . JimF
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'94 S500 Cpe

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